NEW ORLEANS _ Edgar Antonio used to get his jobs in the parking lot of the Dunkin’ Donuts on Jimmy Carter Boulevard in Norcross, Ga. But lately it’s been here in the parking lot of the Shell station at Robert E. Lee Circle, where on a recent morning he wondered about his place in America.

Since shortly after Hurricane Katrina devastated the Gulf Coast, the 26-year-old Honduran had done America’s dirtiest work, cleaning this city’s muck- and mold-caked schools and post offices and gutting its fetid houses.

“It stinks bad, you don’t know how it stinks inside your house,” he said. “We do a hard job, (the) American people, they not doing. … One day, the United States is going to know how much we help.”

Two days later, Antonio was in handcuffs, busted by ICE, the new acronym for the immigration police, and facing deportation or _ because he has been deported before _ prison.

The sudden rush of Latino immigrant workers to the Gulf Coast in Katrina’s aftermath has thrown into sharp relief the existence of an identifiable worker caste, a class of people at once economically essential and socially marginal. It is a national corps of day laborers, and what is happening here provides a glimpse of its inner workings.

It turns on a dime at the whisper of a dollar. Its members, alone or in crews, follow the jobs. They are drawn by word of mouth, dispatched by a nationwide network of staffing agencies, or corralled and deployed by the sometimes shadowy cadre of job brokers and construction subcontractors who provide the link _ and the layers of deniability _ between reputable businesses and the underground economy.

In the months since Katrina, the Gulf Coast has been rife with reports of Latino immigrant workers left stiffed and stranded, working in hazardous circumstances without adequate training or protection, living under bridges and in abandoned cars, in overpriced trailers and overcrowded rooms, or paying $300 a month and $5 a shower to camp in New Orleans’ City Park. All the while, for the many among them who are undocumented, there is the shadow of fear that their sojourn will end as Edgar Antonio’s did _ in handcuffs.

“It’s just a reflection of what’s happening all over the country,” said Tim Bell, executive director of the Chicago Workers’ Collaborative, a day labor advocacy organization.

Just as Katrina, at least for a while, shone a light on the intersection of race and poverty in America, Bell and others hope the immigrants’ fate in New Orleans and along the Gulf Coast brings home the plight of these laborers wherever they gather by dawn in search of a day’s work.

“Every single day, day laborers get into cars with people they don’t know. They take their lives into their hands just to make $10 an hour,” said Steve Smitson, a lawyer with Casa of Maryland, a Hispanic advocacy group in the Washington, D.C., suburbs. “Katrina is a real opportunity to bring the exploitation of these workers out into the open, to bring to the fore how much of our economy depends on the exploitation of these workers.”

Most day laborers, according to UCLA professor Abel Valenzuela, are Latino immigrant men with little command of English. Most are undocumented. In recent years, they have become a growing presence in the construction industry, a perfect fit for employers eager to classify _ or misclassify _ their workers as independent contractors so as to evade unions and avoid providing workman’s compensation or other benefits.

By 2004, Latino immigrants held almost 20 percent of all construction jobs, and 40 percent of the new jobs, according to an analysis of federal data released in May of this year by the Pew Hispanic Center. They made up nearly half of all dry wallers and plasterers, 35 percent of all roofers and a third of hazardous materials removal workers.

New Orleans was only 3 percent Hispanic before Katrina, and in 2000, only four states had a smaller percentage of Hispanics than Mississippi. Now, with no end of work and much of New Orleans’ native labor force spread across the country, the region’s reconstruction is also remaking its demography.

Consider Biloxi, Miss., says Marlon Wade, who with his father owns and runs Wade Roofing and Construction in Mobile, Ala. Biloxi has a population of 50,000, and Wade figures it is going to take that many construction workers to rebuild it.

“Me and my dad were saying this the other day, if it weren’t for immigrant workers, the coast would be in serious trouble,” Wade said. “They’re doing 80 percent of the construction work right now. You could load up trainload after trainload of them and send them back, but you would only be hurting the country.”

Wade has 150 people working along the coast, and “85 percent of them are Mexican.” But he subcontracts for their services, crew by crew. “There’s only one person out of each crew I can speak to,” he said, and that’s the person to whom he makes out the check. “I don’t question where everybody else comes from. They don’t work for me.”

Wade said the immigrants are both more reliable and less expensive than American construction workers, who earn more and party harder. “They get paid on Friday and you might not see them until Monday or Tuesday,” he said, while the immigrant worker is back on the job Saturday morning, “like clockwork. These guys are happy to be here.”

In the immediate aftermath of the hurricane, the Bush administration suspended for 45 days the requirement that employers check the identification of hires, and waived the Davis-Bacon Act requirement that federal contractors pay the prevailing local wage (it was reinstated, effective Nov. 8).

What mattered most, said union leader David Newell, president of the Central Mississippi Building and Construction Trade Council, was that without Davis-Bacon, contractors no longer had to turn in certified payrolls, showing whom they had hired and with whom they had subcontracted, thereby encouraging the use of illegal immigrants at the lowest wages.

For day laborers, Katrina’s timing was impeccable. In most parts of the country, the landscaping season was drawing to a close, construction was ebbing, and snow shoveling was still far away.

“There was a lot of excitement and lot of rumors of getting work after Katrina,” said Casa of Maryland’s Smitson.

Men used his office computer to Google jobs on the Gulf Coast. And, Smitson said, they were well ripe for the plucking when contractors Fredis and Michael Canales, a Maryland father and son, recruited workers to clean the Casino Magic gaming hotels in Biloxi and Bay St. Louis, Miss., at $10 an hour.

But when the men returned from weeks of constant work, some of their checks bounced. Smitson filed suit in federal court on behalf of 35 of them, seeking $200,000 in back pay, overtime and damages.

Michael Canales said he told the men not to cash the checks until he got paid by the company he was subcontracting for (the men who filed suit deny this), and that he said upfront he could not afford overtime.

“They wanted to see us working like slaves,” said Catalino Zepeda, who maintains he is due $2,785.

Meanwhile, in Chicago, Maria Martinez’s husband, father, brother and two brothers-in-law were all recruited to go to New Orleans by a local temp agency. “They came to my house and said, `Don’t worry, Immigration is not going to do anything,”’ Martinez said. “I had a bad feeling.” But the men hadn’t found work in weeks and the mortgage was due on their home in Back of the Yards, a South Side neighborhood.

The men, working and living in the Hyatt Regency next to the Superdome, were paid the promised $12 an hour, but on Nov. 9 ICE _ Immigration and Customs Enforcement _ raided the hotel. One brother-in-law was arrested. The other family members escaped, grabbing a cab back to Chicago. The Honduran driver charged them $1,400, a better deal, Martinez said, than the $500 a head some others paid in what became a small caravan spiriting the undocumented immigrants north.

Martinez, who had become an American citizen in 2001 and has two small children, said the men have since returned to Mexico. After a month in ICE custody, her brother-in-law was deported. The Chicago temp company and the North Carolina restoration firm for which they were working at the Hyatt were not cited.

“The immigrant workers are doing the job,” said Frank Curiel, a Southern organizer for the Laborers’ International Union. The only way to protect them is to organize them, he said.

While it’s often thought that their immigration status might make them more difficult to unionize, Curiel believes the life histories of these people belie that notion. Many of them, after all, are men who lit off from home in their teens, made their way to America and, on their wits and spirit, survived in a strange land.

“What were you doing at 15?” Curiel asks.

Edgar Antonio first made his way to the U.S. with two friends when he was 14, hopping trains, sleeping in bushes and emerging from the Rio Grande dripping wet in nothing but his underwear. He was quickly apprehended, detained for three months, and deported.

He came back, and has lived here nine years _ in San Antonio, in Boston, and Norcross, outside Atlanta. He has been a roofer and floorer, a mover and landscaper.

Working the Shell station corner, he was agile and alert, a haggler with a good grasp of English. “When somebody doesn’t speak English, it’s hard,” he said. He carried his own respirator so he wouldn’t be stuck relying on a surgical mask when the smells got too bad.

The laborers began gathering at the Shell station because it was the first to reopen after Katrina. It was OK with Rose and Lamar Montgomery, who have owned the place 30 years.

“They are willing to rough it to do the work,” she said of the immigrants. “The locals weren’t.” Only a couple of her cashiers have returned. The others are in Denver, Atlanta, Houston and Knoxville.

But across the road, sitting on the circular steps ringing the sky-high monument to Robert E. Lee, Johnny Wiley, a black man from Clarksdale, Miss., glowered at the Latinos in the Shell lot. Wiley, dressed all in black but for his brown cowboy boots, had brought with him a green duffle bag, a child’s pink backpack and a slender dark case containing his pool cue.

He came looking for work, and was shocked by what he found.

“This is New Orleans, our town,” he said. “I didn’t know New Orleans was going to turn into Mexico.”

The next morning word rippled across the Shell lot that ICE was stopping contractors after they picked up workers, and issuing warnings. Just up the street, a truck with Texas plates was pulled over for making an illegal U-turn and the three immigrants inside were lined up against its bed.